A common type of electronic display is the liquid crystal display (LCD). A typical LCD-based display 100 is illustrated in FIG. 1. The display 100 includes an LCD panel 110 and a backlighting structure 120. The LCD panel comprises a grid of liquid crystal elements (or pixels), which transmit light of a specified color when electrically activated. To control the overall brightness of an image on an LCD panel it is often necessary to provide backlighting, as provided by the backlighting structure 120. The backlighting structure 120 includes a cold cathode fluorescent lamp (CCFL) 130 running along one or more side edges of the backlighting structure 120. The CCFL 130 emits light energy into an illumination area behind the LCD panel. A lamp reflector 140 reflects the light energy toward the illumination area, in which a light guide 150 is placed. On the back side of the illumination area is a permanently reflecting material 160 having a reflecting pattern 170. The permanently reflecting material 160 reflects the light energy in the illumination area toward the back side of the LCD panel 110 and thereby provides backlighting to improve the visibility of the LCD panel 110. Positioned between the LCD panel 110 and the light guide 150 are several layers of diffusers 180, including a first plastic diffuser 182, a brightness enhancement film (BEF) sheet 184, a second plastic diffuser 186, and a DBEF (double BEF) sheet 188. The diffusers 180 act to diffuse the light energy in the light guide 150 and distribute it more evenly across the back side of the LCD panel 110 both spatially and angularly.
An LCD element can be made transmissive by applying an appropriate electrical voltage across it. In that way, it is possible to make some or all of the LCD panel 110 transmissive so that a viewer 10 can see through the LCD panel 110, revealing the backlighting structure 120, which is typically illuminated with white light. However, many backlighting structures 120 are neither transmissive nor transparent. When the backlighting structure 120 is non-transmissive or non-transparent, a viewer 10 cannot see an object 20 behind the backlighting structure 120.